90 Cutlass Engine Swap Questions (2.8 to 3.1)

[nnharris]

History: Cracked the block in my 1990 Olds Cutlass. I got a good deal on a 3.1 from a wrecked 1991 Lumina and swapped it for the cracked 2.8. Used all components from the 3.1 with exception of the intake, which is from the 2.8.

Problem: After driving 5 or so miles in the Cutlass with the swapped engine, it become completely unresponsive to acceleration and idles to a stop. If I put it in park, I can repeat the procedure for another mile or so before having to do the same. After checking the computer codes, I found that it reported the MAP sensor as being bad.

Questions: Is it possible that the 2.8 intake is causing the 3.1 to run lean? (I'm not sure that I can get enough miles on it in it's current condition to get telltail signs of it running lean on the plugs.) If it is running lean, any suggestions? Would injectors from a larger displacement 60 Degree V6 compensate? Or would the computer module need to be reprogrammed to acheive the correct Fuel-to-Air Ratio?

[pacman46]

You need a computer fo a newer cutlass that originally had a 3.1, as for the intake, the 2.8 and 3.1 are the same.